Grab your beakers, Bunsen burners, and safety goggles—National Chemistry Week is this week! Starting October 16 through October 22, chemists around the United States will unite in the recognition of the role chemistry plays in everyday life. To encourage this promotion, hBARSCI decided to share some surprising ways chemistry makes your world go ‘round every day.
Onions produce the chemical irritant known as syn-Propanethial-S-oxide, which irritates your eyes when it comes into contact with them, stimulating the eyes’ lacrimal glands so they release tears.
How this works is: first, lachrymatory-factor synthase is released into the air when you cut the onion. Next, the synthase enzyme converts the amino acids sulfoxides of the onion into sulfenic acid. The unstable sulfenic acid rearranges itself into syn-Propanethial-S-oxide. Syn-Propanethial-S-oxide gets into the air and comes in contact with our eyes. The lacrimal glands become irritated and produce tears. Now you know what to blame when you tear up in the middle of meal prep!
You ate it, and now your body must transform that tasty food into the energy your body can use—while getting rid of the parts it can’t. How does your body break down food into energy? Chemistry!
Two types of digestion—mechanical and chemical—work together to break down the food you eat. Chemical digestion is the biochemical process in which larger molecules of food are changed into smaller molecules that can be absorbed into body fluids and transported to cells throughout the body. Chemical digestion is achieved by the secretion of chemical substances, such as enzymes, bile, and acids, along the gastrointestinal (or GI) tract (see image). Although some chemical digestion takes place in the mouth and stomach, most occurs in the first part of the small intestine (also called the duodenum). The chemical substances are secreted by the salivary glands, stomach, and pancreas.
Substances in food that must be chemically digested include carbohydrates, proteins, lipids, and nucleic acids. Carbohydrates must be broken down into simple sugars; proteins into amino acids; lipids into fatty acids and glycerol; and nucleic acids into nitrogen bases and sugars. Once these substances are broken down enough, they can be absorbed and used by cells to create the energy needed to make the proteins, chemicals, and signals responsible for everything that happens inside our bodies.
Check out this Innovating Science kit that lets you expose three nutrients—carbohydrates, proteins, and lipids—to different digestive enzymes for comparison, and then contrast the samples to nutrients with no enzymes by testing to determine effectiveness in digesting the compounds.
Washing your hands has been all the rage the past couple years, brought back into popularity by the pandemic. From the Latin root word for soap, sapo, saponification literally means "turning into soap.” Saponification is a process by which triglycerides are reacted with sodium or potassium hydroxide (lye) to produce glycerol and a fatty acid salt, or soap. The triglycerides are most often animal fats or vegetable oils.
The function of soaps and detergents is to remove grease and dirt by emulsifying the grease (bringing it into suspension). Dirt sticks to clothing and to skin primarily by being adhered to these surfaces with a thin film of oil or grease, which is usually left on the skin after being secreted during perspiration. The soap or detergent removes this film and the dirt can be washed away.
Molecules of soap and detergent contain a nonpolar (hydrophobic) hydrocarbon end and a polar (hydrophilic) end. The nonpolar ends of the molecule surround the tiny oil droplets and are partially dissolved. The polar ends of the molecules are soluble in water and therefore emulsify the entire droplet.
Get even more hands on with our Innovating Science kit that lets you study the properties of soaps and detergents up close! The kit includes experiments for testing pH, examining the effect of soap and detergent on the surface tension of water, and observing foaming ability, fat emulsification, and the performance of soap and detergent in hard water.
Caffeine, easily found in many food products such as coffee, tea, soft drinks, and chocolate, is the most consumed psychoactive compound in the world. The drug is also added to some nonprescription medications, such as pain-relievers and cold remedies.
Caffeine acts as an adenosine receptor antagonist; this means that it blocks adenosine receptors in the brain by taking its place by bonding with the receptors itself. When adenosine cannot be taken up because these receptors are blocked by the caffeine molecule, the body experiences prolonged wakefulness because it does not receive the message to become drowsy, which is what adenosine signals.
